I've mentioned this before, but it's worth mentioning again. If you're tempted to respond to any postings for jobs in Dongguan, such as the one that just appeared for a "high paying job," think it through carefully. The above company for example thinks that 5000 - 6000 qualifies as high paying. Not. Especially not in Dongguan where the cost of living is quite high compared to comparably sized cities in China. More importantly though is that Dongguan is the most polluted place I've ever seen. That is, the air quality is very, very bad. You'll be lucky to ever see the sun there. In the morning you can check out the black cars and see a fine layer of white pollutants that have collected overnight. Yep, you're breathing that stuff into your lungs if you go there.
Avoid it if you value your health and your pocketbook.